The field of surface processing for the excavation of hard rock generally comprises conventional drilling and blasting. Specifically, whether for mining or civil construction, the excavation process generally includes mechanical fracturing and crushing as the primary mechanism for pulverizing/excavating rock. Many of these techniques incorporate the use of chemical explosives. However, these techniques, while being able to excavate the hardest rocks at acceptable efficiencies, are unavailable in many situations where the use of such explosives is prohibited due to safety, vibration, and/or pollution concerns.
An alternate method of surface processing for the excavation of hard rock incorporates the use of electrically powered plasma blasting. In this method, a capacitor bank is charged over a relatively long period of time at a low current, and then discharged in a very short pulse at a very high current into a blasting probe comprised of two or more electrodes immersed in a fluid media. The fluid media is in direct contact with the solid substance or sample to be fractured. These plasma blasting methods however, have been historically expensive due to their inefficiency.